I'm having a problem opening a database

I am working on an application to store documents in a FILESTREAM database. I have created the database and I have inserted a few records into this database using an SQL query. But for some reason I cannot open the database in a Visual Basic application to even get started to manipulate the data.
Here is the code, I have used this basic code in several other applications, and it works fine:

Imports System.Data.SqlClient
Imports System.Drawing
Imports System.IO

Module Program
    Sub Main()
        'Create a connection to the database
        Dim ConStr As String = "Data Source=DESKTOP-UAB5C74\SQLEXPRESS;
            Initial Catalog=I:\MyFileCabinet\MyFileCabinet; 
            Integrated Security=True"
        'Create a new SQLConnection
        Dim con As New SqlConnection(ConStr)
        'Open Database with error catching
        Try
            con.Open()
        Catch ex As Exception
            Console.WriteLine("Open Error" + ex.Message)
            Exit Sub
        End Try
        Console.WriteLine("File Opened")
        'Cleanup
        con.Close()
    End Sub
End Module

When I debug the application, I get the following error:
"Open error, cannot open database "I:\MyFileCabinet\MyFileCabinet" requested by the login
The login failed for user ‘DESKTOP-UAB5C74\Brown’"

I have made sure that user ‘DESKTOP-UAB5C74\Brown’ is the owner of the .dbf file and the log file, and that user has full rights to these files.
I have checked database properties to be sure the connection string was correct.

I have no idea where to go from here, any help would be greatly appreciated.